Vibrio vulnificus was isolated from a blood culture of a 41-year-old male patient with liver cirrhosis. He had eaten raw fish one day prior to the onset of clinical symptoms which included fever, chills, diarrhea and hypotension. He also developed cellulitis of the right leg which developed into a necrotic ulcer. The isolate was a slightly curved gram-negative bacillus and the colony morphology on a TCBS plate was similar to that of V. parabaemolyticus. Acid production from lactose was detected after 2 days of incubation. Other biochemical tests showed typical reactions of V vulnificus. The isolate was susceptible to all of the tested antibiotics except to clindamycin, colistin and penicillin G.
Adult ; Human ; Liver Cirrhosis/complications* ; Male ; Microscopy, Electron ; Septicemia/microbiology* ; Vibrio/isolation & purification ; Vibrio/ultrastructure ; Vibrio Infections/microbiology*

BACKGROUNDVibrio vulnificus (Vv) is an estuarine bacterium that can cause primary septicemia as well as serious wound infections. However, little is known about the mechanisms by which Vv infects dendritic cells (DCs) and its effects on cytoskeleton. In this study, we aimed to investigate the invasion, internalization, and the organelles damage of the cultured dendritic cells (a DC 2.4 strain) during Vv infection.

METHODSThe study model was the cultured DCs infected by a Vv 1.758 strain. Electron microscopy was used to observe the localization of bacteria at the different time points of infection, cell morphology, and the process of organelles changes. The cytoskeleton structure including the microfilaments and the microtubules rearrangement was examined under a fluorescence microscope.

RESULTSThe Vv were pinocytosised into the DC cells through double-sides, and localized at 1 - 2 mm of the inner side membrane. It took 1.3, 1.9, and 3.4 hours to reach the infection ratio of 25%, 50%, and 75%, respectively. Using electron microscopy, the DCs had been observed to have developed chromatin aggregation within 4.0 hours, and significant cytoskeleton structure disruption was noted within 6.0 hours.

CONCLUSIONThe high lethality of Vv infection may be associated with the direct disruption of the DCs cytoskeleton structure.

Animals ; Apoptosis ; physiology ; Cells, Cultured ; Cytoskeleton ; metabolism ; ultrastructure ; DNA Fragmentation ; Dendritic Cells ; metabolism ; microbiology ; ultrastructure ; Mice ; Microscopy, Electron ; Microscopy, Electron, Transmission ; Vibrio Infections ; metabolism ; Vibrio vulnificus ; pathogenicity

OBJECTIVETo study the survival and growth of Vibrio cholerae inside the Acanthamoeba polyphage.

METHODSSurvival and growth of Vibro cholerae O139, co-cultured with Acanthamoeba polyphaga, was observed inside the trophozoites and cysts, using Gram stain and electron microscope.

RESULTSViable O139 was observed inside the amoebal vacuoles in 24 hours. Vacuoles were filled with more bacteria along with the longer period of co-culture. The process of O139 infection with Amoebae would include uptake, formation of O139 vacuole, multiplication, trophozoites lysed and expel under electron microscopy. Some infected trophozoites could subsequently encyst and the surviving O139 could locate in the vesicles inside the cysts.

CONCLUSIONO139 might survive and multiply in the trophozoites and reside inside the cysts of Amoebae, suggesting that Acanthamoebae might serve as one of the environmental hosts of Vibro cholerae.

Acanthamoeba ; growth & development ; microbiology ; ultrastructure ; Animals ; Coculture Techniques ; Colony Count, Microbial ; Culture Media ; Vibrio cholerae O139 ; growth & development ; ultrastructure ; Water ; parasitology

OBJECTIVETo understand the genetic structures and variations of the superintegron (SI) in Vibrio cholerae isolated in the seventh cholera pandemic.

METHODSPolymerase chain reaction scanning and fragment sequencing were used. Sixty toxigenic V. cholerae O1 El Tor strains isolated between 1961 and 2008 were analyzed.

RESULTSSome variations were found, including insertions, replacements, and deletions. Most of the deletions were probably the result of recombination between V. cholerae repeat sequences. The majority of the variations clustered together. The SIs of the strains isolated in the 1960s and 1970s showed more diversity, whereas SI cassette variations in strains isolated in the 1990s and after were lower, with ∼24 kb signature sequence deletion. This indicates the predominant SI in the host during the epidemic in the 1990s and after. The insertion cassettes suggested the mobilization from the SIs of other V. cholerae serogroups and Vibrio mimicus.

CONCLUSIONThe study revealed that structural variations of SIs were obvious in the strains isolated in epidemics in different decades, whereas the divergence was based on syntenic structure of SIs in these El Tor strains. Also, the continuing cassette flows in the SIs of the host strains during the seventh cholera pandemics were displayed.

Cholera ; epidemiology ; microbiology ; Chromosomes, Bacterial ; genetics ; ultrastructure ; Cluster Analysis ; DNA, Bacterial ; genetics ; Electrophoresis, Gel, Pulsed-Field ; Gene Deletion ; Gene Flow ; Genetic Variation ; Humans ; Integrons ; genetics ; Mutagenesis, Insertional ; Open Reading Frames ; genetics ; Polymerase Chain Reaction ; Tandem Repeat Sequences ; Vibrio cholerae O1 ; classification ; genetics ; isolation & purification ; ultrastructure